• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
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    • 专利摘要:
    [00115] Aspects provide for a Whitewater processing system suitable for managing an ejected Whitewater spray during operation of a paper or board making machine. A de-air system may provide for improved removal of air from the whitewater. A calming system may reduce turbulence in a liquid flow, reducing turbulence in the flume. The de-air system and calming system may be disposed together or separately. Certain aspects may be implemented with a turbineused to generate electricity from the whitewater spray). Some aspects may provide for improved handling of variable spray velocities.
    公开号:SE1550683A1
    申请号:SE1550683
    申请日:2015-05-27
    公开日:2016-11-28
    发明作者:Videgren Leif；Engqvist Elin
    申请人:Valmet Oy；
    IPC主号:
    专利说明:

    [3] [0003] To reuse this spray of ejected whitewater, large amounts ofentrained air need to be removed from the water. Typically, the spray isdecelerated and gathered to form a flowing stream of liquid water in a so-called”flume” The flume typically comprises a relatively long channel (e. g., severalmeters or more) through which the water flows relatively slowly, so that airbubbles can rise to the surface prior to reuse of the water. The flume is typicallyseveral meters (even tens of meters) long and over a meter (even several meters)wide. Because flow through the flume should be slow (allowing air bubbles torise to the surface), the flume typically has a very shallow slope away from theforming section toward the fan pumps used to recycle the flume water. Suchlong flume lengths are typically necessary to maximize the tendency of airbubbles to rise up out of the flume water. It is desirable to shorten flume length,and so it is desirable to remove air (e. g., from the ejected whitewater) as quicklyand efficiently as possible.
    [4] [0004] The reuse of water (e. g., to make additional stock with addedsuspended material) may be improved with more efficient air removal from thewater. It is desirable to produce an efficient de-aeration process (e. g., to reduce2 127534011 (caim)complexity, cost, and/or energy consumption) associated with recycling thewhitewater.
    [5] [0005] EP 1 424 437 A1 describes collecting drainage water from aforming roll in a twin-wire former of a paper machine. U.S. Pat. No. 4,714,522discloses a system in which whitewater is caught in a whitewater trough whichis provided with deflection vanes. U.S. Pat. No. 4,028,174 discloses a curveddeflector for intercepting high Velocity sprays of liquids. U.S. Pat. No. 6,096,120discloses a double acting deaeration vessel. PCT patent application no.PCT/IT2007/000600 describes a wet forming paper machine with systems toreduce turbulence.
    [6] [0006] US Patent No. 8,784,538 describes a solution in which a firstchamber part comprises a guide wall portion for redirecting drainage water in apredetermined second flow direction that differs from the first flow direction,said guide wall portion being formed by a plurality of curved guide walls whichdefine a plurality of curved and substantially parallel flow channels for thedrainage water and that the guide walls are arranged to interact with thedrainage water in such a way that the drainage water is decelerated and air isforced out of the drainage water; and two substantially planar end walls, whichare substantially parallel to the first flow direction and which are arranged onrespective sides of and substantially orthogonally to the guide walls, wherein3 127534011 (caim)each end Wall of at least one of the flow channels exhibits an opening thatcommunicates with the flow channel for removing at least part of the air, whichhas been released from the drainage water in the flow channel by saidinteraction, from the first chamber part.
    [7] [0007] The disclosures of references described herein are incorporatedherein by reference. The present disclosure also incorporates by referenceSwedish patent applications no 1450812-1, filed Iuly 1, 2014, 1450882-4, filed ]uly9, 2014, and 1450823-8, filed ]uly 2, 2014.
    [8] [0008] Many prior art solutions present certain challenges, particularlyfor modernized systems. FIGS 1A and 1B illustrate prior art. FIG. 1A illustratescertain aspects of the deaeration unit disclosed in US 8,784,538. A guidingportion 2 directs drainage water flow in the machine cross direction out of theforming section, and comprises a plurality of substantially parallel, curveddeflectors 4, which direct the drainage water to an outlet 34 of guiding portion 2.
    [9] [0009] A deaeration unit 3 has its extension substantially in the crossdirection of the paper machine. The deaeration unit 3 includes a plurality ofdividing guide walls 10 of sheet metal and roof portion 23, which exhibit acurved or bent shape. Each guide wall 10, 23 exhibits a free upstream end 11 thatis arranged at the inlet 8 (which receives drainage water from the guidingportion 2 via outlet 34).4 127534011 (caim)
    [10] [0010] FIG. 1B illustrates detail of the interface between the outlet 34 ofthe guiding portion 2 and the inlet 8 of the deaeration unit 3. At this interface,the trailing edges of the curved deflectors 4 are oriented across the free upstreamends 11 of the guide walls 10 in the deaeration unit 3. This orientation causesflow streams in the channels exiting the guiding portion 2 to be ”bisected” or”chopped” by the free upstream ends 11 of guidewalls 10. Such choppingincreases turbulence and mixing as the spray ”bounces off” these surfaces (e. g.,edges between the guiding portion 2 into the de-aeration unit 3). Additionally, asingle channel in the guiding portion ejects water and air into a plurality ofchannels in the deaeration unit, and a single channel in the deaeration unitreceives water and from a plurality of channels in the guiding portion. This”criss-cross” orientation provides for fluidic communication among channels(e. g., between channels in the guiding portion, 2 between channels in the de-aeration unit 3, and their combinations), as shown by the schematic arrows inFIG. 1B. With separate channels in fluidic communication, air pressurethroughout the channels is expected to be substantially equal.
    [11] [0011] A paper machine may include a turbine, for example asdescribed in US Patent No. 6,398,913. A turbine disposed in the flow ofwhitewater after it has passed through the forming wire may recover energy5 127534011 (caim)from the whítewater (e. g., to generate electricity with a generator powered by theturbine).
    [12] [0012] Many forming sections generate a ”mist” of fine droplets ofliquid. Typically, these droplets decelerate quickly, and spread around theforming section (and even throughout the room) via convection of air currents.The mist may deposit on surfaces (e. g., floors, steps) and render them unsafe. Amist may comprise residual fibers. A mist may deposit as a ”slime” orotherwise form a slippery surface. A deposited mist may clog or otherwisedegrade Various surfaces (e. g., parts of the machine). A mist may prevent a useror inspector from efficiently seeing various parts of the machine. In some cases,a mist can create a sheet break (a costly manufacturing defect). It is desirable tominimize mist formation.6 127534011 (caim)SUMMARY OF THE INVENTION
    [13] [0013] Various aspects may provide for improved deaeration ofwhitewater. A de-air system may remove air (e. g., by segregating a spray intoliquid and gas phases). Segregation may enable the use of different forces on thedifferent phases. A de-air system may comprise one or more channels designedto generate centrifugal forces within a liquid phase. These forces may enhancethe removal of air bubbles from the liquid. Centrifugal forces within the liquidphase may cause gas bubbles to segregate to a gas/liquid interface. Pressureand/or flow control of the gas phase may be used to extract gas more efficiently.
    [14] [0014] A calming station may reduce turbulence (e. g., in a liquidcomprising gas bubbles), which may enhance air removal in a flume, (e. g., byminimizing the ”recirculation” of these bubbles deep into the flume viaconvection). A calming station may be designed to accommodate variable liquidflow velocities (e. g., that may occur when machine operating conditions change,such as changing from a first tissue type to a second tissue type). A calmingstation may be designed to operate with a turbine, particularly an adjustableturbine, and may comprise a gate and/or baffle designed according to a specificflow pattern (of condensed liquid) associated with the turbine (particularly avariable flow rate). An apparatus (e. g., a calming station) may include a gate(e. g., an adjustable gate, a patterned gate, and the lil7 127534011 (caim)management of different flow velocities. An apparatus may include a baffle,particularly a baffle comprising one or more holes, which may enhance fluidflow (e. g., reduce turbulence). An apparatus may comprise a cleanout (e. g.,above waterline or below waterline). A cleanout may include a suctionmechanism configured to extract material from within the apparatus (e. g., a tubewith holes). An apparatus may include a baffle and/or a gate shaped to inducean eddy in a flowing liquid, which may locally enhance settling. A cleanout maybe disposed in the eddy, such that material within the eddy may be readilyremoved. A de-air system and calming station may be used together orseparately; each may be implemented in a machine comprising a turbine orwithout a turbine.[0015] A de-air system for processing a whitewater spray ejected froma forming wire in a forming section of a paper machine having a machinedirection may comprise one or more channels. A system may comprise first andsecond channels with substantially no fluidic communication between thechannels (e. g., between the inlet and outlet of each channel). A first channel maybe defined at least in part by first walls that are shaped to direct a first portion ofthe whitewater spray away from the machine direction, preferably toward a sideof the paper machine, such as in a cross direction. The first channel may be openat a first entrance proximate to the forming wire and may terminate at a firstg 127534011 (caim)liquid outlet. The outlet may be defined at least in part by first terminal edges ofthe first walls, which may be configured to extend beneath a surface of liquidwater at a flume level during operation of the machine, such that liquid may passout of the outlet but gas may not pass into the channel via the outlet. A first airoutlet in the first channel may provide for air evacuation from the first channel,preferably by a pump or fan or other suitable air movement apparatus.
    [16] [0016] The system may comprise a second channel defined at least inpart by second walls shaped to direct a second portion of the whitewater sprayaway from the machine direction toward a side of the paper machine. Thesecond channel may be open at a second entrance proximate to the forming wireand terminate at a second liquid outlet defined at least in part by second terminaledges of the second walls, which may be configured to extend beneath a surfaceof liquid Water at a flume level. A second air outlet in the second channel mayprovide for air evacuation from the second channel, preferably by a pump or fan,which may be the same that of the first channel or different.
    [17] [0017] In some embodiments, a system has a plurality of channels andis designed to minimize (e. g., prevent) substantial fluidic communicationbetween the channels (e. g., except for at the inlets and possibly air outlets). Anoverflow edge or other suitable apparatus may be used to fix a flume level suchthat liquid may exit the channels via the liquid outlets. Terminal edges of9 127534011 (caim)Channels may be immersed below the surface of the liquid, so that gas isprevented from passing into the Channels via the liquid outlets. Certainembodiments Comprise a plurality of Channels with no substantial fluidiccommunication between the Channels.
    [18] [0018] Air outlets for each channel may be used to evacuate air fromthe Channels. In some embodiments, different evacuation rates are used fordifferent air outlets. First and second air outlets may have different sizes. AChannel that benefits from increased air evacuation (e. g., an outer channel) mayhave a larger air outlet and/or a higher pumping speed. A channel may have anoutlet having an adjustable size.
    [19] [0019] In some cases, a first channel includes a first entrance that isdisposed, laterally with respect to the machine direction, to receive whitewaterspray from an outer portion of the forming wire. A second channel may have asecond entrance disposed to receive spray from an inner portion. The firstchannel may have a higher evacuation rate than the second channel, which maymaximize the removal of ”mist” around the forming section. In some cases, thefirst channel may have a lower evacuation rate.
    [20] [0020] An air outlet, particularly a plurality of the air outlets, may bedisposed in a ceiling of its respective channel, which may increase thepreferential removal of gas (vs. liquid) via the air outlet. In some cases, at least10 12753,1011 (Calm)one outlet is located, With respect to the machine direction, closer to an upstreamwall than to a downstream wall of its respective channel.
    [21] [0021] Momentum of the whitewater spray may be used to segregate awhitewater spray into liquid and gas phases. Momentum may be used togenerate centrifugal forces in a liquid phase that segregate the liquid and gas intoseparate parts of a channel (e. g., the liquid to the outside of a curve, and the gasto the inside of the curved). An air outlet may be located in a parts that isexpected to be associated with gaseous, rather than liquid, flow, and vice versa.Momentum may be used to drive gas bubbles out of the liquid.
    [22] [0022] A de-air system may comprise one or more channels havingsubstantially vertical side walls. A majority of the side walls may be vertical.Substantially all of the side walls may be vertical. Certain channels include oneor more optional internal walls within the channel to guide spray, liquid, and/orgas. In an embodiment, internal walls are disposed relatively far ”downstream”in the channels, (e. g., after segregation of the spray and/or extraction of the gasfrom the liquid). In an embodiment, internal walls are disposed relatively far”upstream” and are oriented to smoothly direct spray down the channels withminimal ”bounce back” of spray from the wall.
    [23] [0023] A de-air system may comprise one or more channels shaped toredirect whitewater spray away from the machine direction, particularly toward1 1 12753,10l1 (Calm)a lateral direction, particularly a cross direction. The channel may be defined atleast in part by channel walls, and including an entrance, air outlet and liquidoutlet, wherein less than 5% of a cross sectional area of the channel, preferablyless than 1% of the cross sectional area, preferably less than 0.1%, preferablysubstantially none of the cross sectional area, is intersected by a free upstreamend of a part.
    [24] [0024] A calming station may be configured for use with a formingsection of a paper machine to reduce turbulence in a liquid flowing into a flumeof the paper machine. A calming station may be combined with a de-air station.A calming station and a de-air station may be implemented independently. Awhitewater processing system may comprise a de-air system and a calmingstation.
    [25] [0025] A calming station may include a liquid inlet, a liquid outlet, anda gate between the inlet and outlet. The gate may comprise an adjustable gateconfigurable among two or more different positions that alter a flow (e. g., ofliquid) through the calming station in different ways. The gate may comprise afirst portion having a first pattern of slats, gaps, or holes, and a second portionhaving a second pattern of slats, gaps, or holes. A gate may have a first regionhaving a first pitch of slats, gaps, or holes through the gate (e. g., in a direction offluid flow through the gate) and a second region having a second pitch. An12 127534011 (caim)adjustable gate may have different patterns or regions of slats, gaps, holes,and/or pitches. A pattern of slats, gaps, holes, and/or pitch may varyhorizontally, vertically, and/or through the gate.
    [26] [0026] A calming station and/or a de-air system may include one ormore gates (e. g., a first gate comprising an adjustable gate and a second gatecomprising a gate with different portions, pitches, and the like). In some cases, afirst portion of a gate (adjustable or not) of a calming station has a first pattern ofslats, and a second portion of the gate has a second pattern of slats. A firstportion of slats may have a first pattern and/or a first pitch (e. g., with respect tofluid flow through the slats) and a second portion may have a second patternand/or pitch.
    [27] [0027] A calming station and/or a de-air system may comprise one ormore baffles, particularly at the bottom of the calming station/de-air system. Abaffle may be disposed and/or shaped to enhance fluid flow through the calmingstation. A baffle may reduce a velocity of the fluid. A baffle may redirect thefluid in a way that improves the extraction of air from the fluid. A baffle may beused to dissipate momentum of a liquid flowing through the calming station. Abaffle may comprise one or more holes. A pattern of slats, gaps, holes, pitches,and/or other features may vary laterally and/or vertically across the baffle.13 12753,10ll (Calm)
    [28] [0028] A baffle may be integrated into a system in a relatively fixedway (e.g., welded, bolted). A gate may be relatively easily replaceable by a user.For example, a gate may be mounted near a hole shaped to allow the gate to bemoved in and out of the system.
    [29] [0029] A de-air station may include a spray guide. A spray guide forredirecting a whitewater spray ejected from the forming wire may comprise oneor more channels shaped to redirect the whitewater spray from the machinedirection to a lateral direction, preferably a cross direction. The channels may bedefined at least in part by channel walls comprising side walls for which amajority, preferably substantially all, of each channel side wall is substantiallyvertical. Vertical walls may reduce manufacturing complexity. Vertical wallsmay enhance the conversion of momentum in the machine direction tomomentum in the cross direction.
    [30] [0030] A spray guide may include one or more channels defined atleast in part by channel walls, entrances to the channels, and liquid outlets fromthe channels. For at least an upstream portion of the channel (e. g., in a region ofthe channel where the spray of liquid has not been segregated into gas and liquidphases), fewer than 10% of the channels, preferably none of the channels, may beintersected by a component that disrupts fluid flow through the channels (e. g., afree upstream end of a part such as a sheetmetal part). A free upstream end of a14 127534011 (caim)part may be a portion of the part that faces directly into fluid flowing throughthe channel. For example, at least a portion of the surface of the part may becharacterized by a surface normal that is parallel to and in opposite direction of aflow vector of the fluid intersecting the portion. The minimization (andparticularly elimination) of such free upstream ends may enable a smoothtransition of spray momentum (from the headbox/forming roll) into linearmomentum. Linear momentum may be used to segregate the liquid and gasphases, Whereas random ”mixing” of liquid and gas phases (as the spray scattersoff surfaces intersecting the channel) may not improve air removal (and mayinhibif a).
    [31] [0031] A roof drain may include a roof shaped to collect drippingwater (e. g., residual water from the forming wire). A roof may be angled towarda gutter, Which may terminate in a drainage hole, optionally With a downspout.
    [32] [0032] A method may comprise using curved channels and thedownstream momentum of the whitewater to induce centrifugal forces in thewhitewater. These forces may enhance the segregation of the liquid (e. g., to theoutside of the curve) and gas (e. g., to the inside of the curve). The method maycomprise evacuating the gas phase of the segregated whitewater (e. g., pumpingthe air out). The air may be pumped out proximate to (e. g., immediately15 127534011 (caim)downstream of) a region of the channel that induces a maximum centrifugalforce on the liquid flowing in the channel.
    [33] [0033] A method for removing air from Whitewater in a formingsection of a paper machine may comprise dividing a spray of Whitewater from aforming wire among a plurality of Channels, each channel having a liquid outletcomprising terminal edges of walls of the channels, setting a flume level suchthat the terminal edges are immersed in the flume to an amount sufficient toprevent substantial flow of air into the channels from the liquid outlets, andevacuating the air in the channels using a pump, preferably using a channelconfiguration in which the only fluidic communication between the channels isprovided at the entrances to the first and second channels.
    [34] [0034] Certain implementations include a turbine configured toharvest energy from the Whitewater spray. A de-air station may be disposeddownstream of the turbine. A calming station may be disposed downstream of aturbine (e. g., downstream of a de-air station). A de-air station and/or a calmingstation may be designed to accommodate Variable flow velocities, as may occurin a turbine implementation (e. g., When the turbine is engaged/disengaged).16 127531011 (Calm)BRIEF DESCRIPTION OF THE DRAWINGS
    [35] [0035] FIGS. 1A and B illustrate prior art.
    [36] [0036] FIG. 2 is a schematic illustration of an exemplaryimplementation.
    [37] [0037] FIGS. 3A and 3B illustrate an exemplary embodiment.
    [38] [0038] FIG. 4 is a schematic illustration of a plan View, according tosome embodiments.
    [39] [0039] FIGS. 5A and 5B illustrate exemplary embodiments of channelgeometries.
    [40] [0040] FIGS. 6A and 6B illustrate aspects of a calming station,according to some embodiments.
    [41] [0041] FIG. 7 A is a schematic illustration of multiple gates, accordingto some embodiments.
    [42] [0042] FIG. 7B is a schematic illustration of a baffle, according to someembodiments.
    [43] [0043] FIGS. 8A-8F illustrate exemplary patterns, according to someembodiments.
    [44] [0044] FIGS. 9A-F illustrate various slat cross sections, according tosome embodiments.17 127534011 (caim)
    [45] [0045] FIG. 10 is a schematic illustration of adjustable slats, accordingto some embodiments.
    [46] [0046] FIG. 11 illustrates a gate having slats With varying pitches,according to some embodiments.
    [47] [0047] FIG. 12 illustrates an exemplary implementation With a turbine,according to some embodiments.13 127534011 (caim)DETAILED DESCRIPTION OF THE INVENTION
    [48] [0048] A whitewater spray may be gathered and/or condensed to aliquid in one or more channels. Channels may be integrated into a spray guidesystem and/or a de-air system. Curves in the channels may impart centripetalforces to the liquid. Centrifugal forces in the liquid may cause air bubbles in theliquid to ”rise” to the surface (e. g., in an ”inward” direction opposite that takenby the denser Water, as in a centrifuge). An apparatus may have one channel.An apparatus may have two, three, four, six, eight, ten, or even twelve or morechannels.
    [49] [0049] Air may be removed in a de-air system. In some cases, air isremoved with one or more pumps (e. g., fans), which may evacuate air in achannel (e. g., reducing air pressure Within the channel to enhance air removal).Centrifugal forces may enhance the removal of air bubbles from liquidwhitewater. Air removal may be enhanced with a combination of centrifugalforce (acting on the liquid phase to drive out air bubbles) and reduced airpressure/increased air evacuation rate (to remove the air bubbles).
    [50] [0050] In an embodiment, a channel ”smoothly” causes the spray tosegregate (onto a curved wall) and flow along the Wall. For example, a surfacemay be designed such that the (predicted) angle of attack of incoming spray doesnot exceed 30 degrees, and preferably does not exceed 20 degrees, or even 1019 12753,1011 (Calm)degrees. The design may cause the spray to collect along the surface, forming afilm, rather than ”bounce off” the surface. Preferably, the momentum of the filmis maintained as the film follows a curved portion of the wall, Where centrifugalforces drive (e. g., large) air bubbles toward the inside of the curve. Subsequently(e. g., after the bubbles have been segregated out of the liquid), air is removedfrom above the liquid. Smaller bubbles not removed by centrifugal forces maybe removed in the flume.
    [51] [0051] Vertically oriented Walls (Which typically curved) may inducean axial acceleration that drives air bubbles inwards (With respect to a channelradius) When a film of water travels along the outside Wall of the channel.Channels may be designed such that liquid momentum causes the liquid flowingthrough a channel to preferentially flow along a portion (e. g., the outside of acurve). An air outlet from the channel may be preferentially located in anotherportion (e. g., near the inside of a curve) Where liquid is not preferentially located.An air outlet may be in a ceiling of the channel. Vertically oriented walls mayimprove the manufacturability of a device (e. g., as opposed to devices havingwalls With complex curvatures).
    [52] [0052] Some machines do not generate a uniform spray density(laterally) across the forming Wire. For example, an ”outer part” of the formingsection may generate a spray having more air and/or smaller droplets than that20 12753,1011 (Calm)generated in an ”inner part” of the forming section. The spray from the outerpart may be more like a ”mist” of fine droplets that quickly decelerate. This mistmay spread laterally, vertically, and the like (creating almost a ”fog” around theforming section). This mist may condense, and even ”rain” on the variousapparatus around and within the forming section. In contrast, the spray in theinner part of the forming section may comprise larger droplets having significantforward momentum that readily carries them into the channel.
    [53] [0053] To accommodate variable spray densities/velocities/dropletsizes, various embodiments comprise two or more channels that are substantiallyfluidically separated. An outer channel may be located proximate to an outerpart of the machine (e. g., having a more ”mist-like” spray that requires more of a”vacuum cleaner” effect to prevent its dispersal around the machine. An innerchannel may be located toward the center of the machine, (e. g., where themomentum of the spray is sufficient to propel the spray into the channel).
    [54] [0054] Pumping speed control over the separate Channels may beimplemented in a variety of ways. Channels may have different sized air outletsand/or adjustable air outlets to improve the efficiency of air removal with respectto pump energy. Channels may have different pumps or fans (e.g., outerChannels may have a higher speed pump than that pumping inner Channels)
    [55] [0055] A Calming station may be Configured to reduce turbulence inliquid water (e. g., prior to the flume). The removal of small air bubbles in aflume may be improved by reducing convection in the flume (which mightcirculate small air bubbles back down to the bottom). A Calming station mayreduce turbulence in the liquid water ejected from the forming section (e. g., via ade-air system), which may improve air removal in the flume. A Calming stationmay increase the uniformity of flow of the water. For example, in a computersimulation of expected flow velocities (e. g., over a cross section of the flowingliquid) a Calming station may reduce the variability in the flow velocity vectors(e. g., in a lateral direction, a vertical direction, orthogonal to the flow direction,and the like). In some machines, an inner channel of an apparatus directingwater flow out of the machine direction comprises a smaller radius of curvature,and an outer Channel has a larger radius of curvature. Water flowing from the22 127534011 (caim)inner channel may have a higher Velocity. A calming station and/or de-airsystem may comprise a baffle and/or gate having a first pattern for water flowingfrom the ”inner channel” and a second pattern for water flowing from the outerchannel.
    [56] [0056] Certain aspects may incorporate a turbine. A turbine may bedisposed (e. g., immediately after the forming wire) to harvest the kinetic energyof the whitewater spray. During machine operation, engagement of a turbinetypically results in decreased whitewater velocities (post-turbine), anddisengagement of the turbine results in increased whitewater velocities (post-turbine). Certain aspects of a de-air station and/or a calming station may providefor improved management of these different flow velocities. Apparatus may beadjusted between a first position (for high velocity flow) and a second position(for low velocity flow). Apparatus may be inserted or removed to accommodatedifferent velocities. Apparatus may have patterns designed to accommodatevariations in the flow field that occur as the aggregate flow velocity changes.
    [57] [0057] FIG. 2 is a schematic illustration of an exemplaryimplementation. A typical (e. g., paper or board) machine 1 may be characterizedby a machine direction 11 and a cross direction 22. A forming section 10 of thepaper machine may include a head box 12, which injects stock 30 onto a formingwire 14 as it moves around a forming roll 16. The stock may form a web 40 (e. g.,23 127534011 (caim)of Wet paper, board, and the like). A spray of Whitewater 50 is typically ejectedthrough the forming Wire, and recycled via a flume 18. A Water level in theflume 18 may be maintained by an overflow edge 19 or suitable equivalent.
    [58] [0058] The Whitewater spray is typically ejected at high velocities. Insome implementations, an optional turbine 20 may be used to harvest energyfrom the Whitewater. Turbine 20 may be coupled to a generator 21 to generateelectricity using this energy.
    [59] [0059] A modern turbine implementation may involve some operatingtime in Which the turbine is engaged, and other times during Which the turbine isnot engaged. When engaged, the turbine typically results in a substantialslowing of the Whitewater spray (after the turbine). When the turbine isdisengaged (e. g., during turbine maintenance), the Whitewater may have a muchhigher (or ”native”) spray velocity. The large difference in velocities (andmomenta) between these ”engaged” and ”disengaged” configurations maycreate significant challenges with respect to Whitewater handling. A Whitewaterhandling system configured only to manage the ”low speed” Whitewater from anengaged turbine may be overwhelmed by the ”high speed” Whitewater When theturbine is disengaged, and vice versa. Various aspects described herein providefor improved handling of Whitewater across a range of Whitewater sprayvelocities. In some cases, one of a de-air system and a calming station are24 127534011 (caim)designed to handle Variable spray velocities. In an embodiment, both the de-airsystem and the calming station are configured to handle Variable sprayvelocities, and they may be designed to cooperate in this handling of variablevelocities.
    [60] [0060] A paper machine may comprise one or more components of aWhitewater processing system 200. System 200 may include one or more of a de-air system 300, a calming station 600, gate (e. g., an adjustable and/or replaceablegate), a baffle (716), gates and/or baffles having different patterns of slats, holes,gaps, pitches, and the lil
    [61] [0061] In FIG. 2, an embodiment comprises a de-air system 300 and acalming station 600. The spray of Whitewater 50 may be received from theforming section (which may include turbine 20) by de-air system 300. De-airsystem 300 may collect, ”condense” and otherwise capture the spray. De-airsystem 300 may redirect the spray out of the machine direction (e. g., laterally,such as in cross direction 22) for handling. De-air system 300 may remove airfrom the liquid Whitewater (e. g., with a pump 302, such as a fan evacuating airoutlets of the de-air system (FIG. 4).25 127534011 (caim)
    [62] [0062] Liquid water may be collected into flume 18, which may have aflume level controlled by an overflow edge 19 or other suitable apparatus. Insome cases, liquid water may flow directly from de-air system 300 to flume 18.
    [63] [0063] FIGS. 3A and 3B illustrate an exemplary embodiment. FIG. 3Ais an illustration in which certain outer surfaces have been removed to showinteriors. FIG. 3B illustrates a view from the direction annotated A-A in FIG. 3A.In the embodiment shown in FIGS. 3A and 3B, a plurality of channels is used toredirect respective portions of whitewater from the forming wire spray (not26 12753,1011 (Calm)shown) to the flume (not shown). In some cases, entrances to the channels arelaterally distributed across the machine, so that a first portion of the spray (e. g.,an outer portion) travels through a first channel, and a second portion of thespray (e. g., an inner portion) travels through a second channel.
    [64] [0064] In some implementations, the density of the whitewater spray(e. g., a relative concentration of water in air) is not uniform across the machine.For example, an outer portion of the spray (associated with a side of the web)may have a higher amount of air than an inner portion. The outer portion of thespray may require the removal of additional air (from its associated water) thanthe inner portion.
    [65] [0065] In FIGS. 3A and 3B, a first channel 310 may be defined by one ormore first walls 316. Walls may include a ceiling and/or floor of the channel (notshown). First channel 310 is open at a first entrance 312 (near, preferably facing,the spray coming from the forming wire) and may receive a first portion of thespray coming from the forming wire. A second channel 320 is open at a secondentrance 322, and may receive a second portion of the spray. Walls 316, 326 ofthe channels may be shaped to direct the respective portions of the spray downtheir respective channels, typically in a direction away from the machinedirection (e. g., in the cross direction). At least a portion of the walls may bevertical).27 127534011 (caim)
    [66] [0066] The spray (also called a Water jet) coming through the formingwire may comprise a gas (e. g., air) and a liquid (e. g., Water). One of these phasesmay be a majority phase (e. g., a continuous phase). A phase may be a minorityphase (e. g., droplets in air, bubbles in liquid). Both liquid and gas may be presentin approximately equal amounts, and both phases may be substantiallycontinuous. There may be more liquid than gas; there may be more gas thanliquid. The spray may be a highly mixed, high Velocity, multiphase material.The spray may comprise a small amount of residual material from Which theweb is fabricated (e. g., fibers).
    [67] [0067] As the spray flows through the channels, it may be condensed,gathered, and/or segregated into separate phases by the de-air system. Aseparate phase may include a liquid phase, which may include discrete bubbles.A separate phase may include a gas phase, which may include discrete droplets,such as mist. The channel walls may be designed to induce phase separation inthe spray into a majority liquid phase (e. g., water with bubbles) and a majoritygas phase (e. g., air, possibly With a mist of fine droplets).
    [68] [0068] In some embodiments, this phase separation may be used toimplement different removal methods for the different phases. A substantiallyliquid phase (e. g., the condensed water) may be de-aired Within the de-air stationand/or flume. The gas phase may be used as-is, and/or de-aired in a droplet28 12753,1011 (Calm)separator and/or other apparatus designed specifically for the removal of fineparticulates from gases (e. g., a cyclone, a porous trap, and the like). A dropletseparator may be disposed between a gas outlet and a pump/fan evacuating thegas outlet.
    [69] [0069] The channels may include separate outlets for gas and liquid.These outlets may be implemented in a way that results in the segregated gas(within each channel) being preferentially removed through its respective gasoutlet, and the segregated liquid being preferentially removed through itsrespective liquid outlet. In FIGS. 3A and 3B, first channel 310 terminates atliquid outlet 315, and second channel 320 terminates at liquid outlet 325. Liquidoutlets may comprise a ”face down” orientation of the channel walls, in whichthe terminal edges 318, 328 of the channel walls descend below the flume level(which may be set by the overflow edge, not shown). Such a configuration ofoutlets may create a ”water trap” that allows water to exit the channel, but doesnot allow gas phase flow into the channel. For example, liquid outlet 315 mayprevent the flow of a gas phase into channel 310, yet allow the flow of the liquidphase out of channel 310. This ”water trap” may use the mass of the water to”seal” the channel, allowing for evacuation of the gas phase.
    [70] [0070] Second channel 320 may include its own second entrance 322open to its respective portion of the whitewater spray. Second walls 326 may29 127534011 (caim)concomitantly direct the second portion of the spray to a second liquid outlet325. Second terminal edges 328 of second walls 326 may be immersed in waterat the flume level, such that second liquid outlet 325 allows the egress of liquidfrom second channel 320, but does not allow entrance of gas into second channel320. A wall and/or edge of a first channel may also be a wall and/or edge of asecond channel (e. g., a wall between two channels).[0071] Gas outlets may be disposed in each respective channel (e. g., inthe ceilings of the channels, not shown). Typically, gas outlets are disposed at apoint in the channel after which the spray has been condensed and segregated,such that the gas phase may be removed independently of the liquid phase. Insome implementations, a wall geometry is chosen that does not substantiallydisrupt (e. g., maximizes) the forward velocity of the spray (in the machinedirection) then gradually induces an acceleration (e. g., laterally). A channeldesign may be chosen that changes spray direction ”smoothly” with minimalloss of momentum, such that the kinetic energy of the spray is efficientlyconverted to centrifugal forces within the liquid.[0072] Centrifugal forces may ”force” gas bubbles out of the liquidphase. These forces may induce segregation of the gas bubbles (toward thecenter of the curve) for subsequent removal. The walls may induce laminar flowin the stream. In some embodiments, there are no features in the channels that30 127534011 (caim)induce turbulence or mixing in the stream (e. g., no ”criss-cross” orientations offirst Channels meeting second Channels).
    [73] [0073] The gas phase may be removed may be via gas outlets (e. g., airoutlets 410, 420, FIG. 4) in the Channels. Typically, incoming spray Will generatea positive pressure Within the Channels (via their entrances). The spray may besegregated into liquid and gas phases within the Channels. The liquid phase mayexit the Channels through the liquid outlets (but not the gas outlets), and the gasphase may exit the Channels through the gas outlets (but not the liquid outlets).Such a Configuration may ”seal” each channel, such that a Vacuum pump may beused to evacuate the gas phase from each channel.
    [74] [0074] Typically, a pumped outlet is located far enough downstream(in the Channel) that segregation (e. g., via Centrifugal force) has been maximized(and thus as much gas as possible removed) prior to gas phase evacuation. Insome Cases, the outlet is located in a part of the Channel Where the liquid phaseundergoes substantially laminar flow (e. g., the liquid is not being redirected in aWay that induces turbulence, as may be done in a Calming station to reduceliquid Velocity.
    [75] [0075] Certain embodiments include a single Channel. In a multi-channel embodiment, the Channels may be fluidically separated between theirrespective entrances and outlets. In an implementation, the machine is operated31 12753,10l1 (Calm)at a flume level that results in terminal edges of the channel(s) 318, 328 beingimmersed far enough below the flume level that they ”seal” the channels to gasflow (while allowing liquid flow into the flume). In such an implementation,first channel 310 and second channel 320 may be fluidically separated (after theirentrances) such that there is substantially no fluidic communication between thechannels. As a result, the gas pressures in channels 310 and 320 may bemaintained independently of each other. In an embodiment, a lower gaspressure (and/or higher pumping speed) is created in an outer channel (e. g., 310)vs. that in an inner channel (e.g., 320). Such an implementation may improve theremoval of (the larger amounts of) air in the outer portions of the whitewaterspray.
    [76] [0076] Some embodiments do not require fluidic independencebetween channels (and may not even require multiple channels). In certainimplementations, a flume level may be set that does not result in terminal edges318, 328 descending below the flume level.
    [77] [0077] For the purposes of this specification, ”substantially” is definedas ”close enough to this condition to provide for an effect caused by thiscondition." For example, there may be no substantial fluidic communicationbetween two channels, even though small gaps may be present between thechannels (e. g., for manufacturing convenience). These gaps may be sealed by32 12753,10l1 (Calm)liquid flow and/or not be large enough to have an effect on the (lack of) fluidiccommunication between Channels. For example, a small gap between Channelsmay be present, but With suitably high pumping speed (evacuating the gasbetween Channels) the Channels may be, for practical purposes, fluidicallyindependent. A ”substantially vertical” wall may be slightly off vertical. A”substantially planar” wall may be slightly Curved.
    [78] [0078] FIG. 3A illustrates certain Components of an optional roof drain1200 (FIG. 9). A calming station, a de-air system, and/or other apparatus ”insidethe loop” of forming wire may Comprise a roof drain to gather water (e. g., fallingoff the forming wire or fabric above the apparatus). A roof drain may comprise aroof or other surface to Catch water, a gutter (e. g., to Collect the caught water),and a drain (e. g., to drain the collected water).
    [79] [0079] FIG. 4 is a schematic illustration of a plan view, according tosome embodiments. In FIG. 4, the right hand side of de-air system 300 is shownwithout its respective ceiling. The middle part (with features 410-440) showschannel walls comprising Ceilings 412 (in first Channel 310) and 422 (in secondChannel 320). A leftmost portion of de-air system 300 includes a ”turn down”region that directs flow to the respective liquid outlets (in this example,downward with respect to machine direction, or ”into the page”).33 127534011 (caim)
    [80] [0080] Gas outlets 410, 420, 430, 440 in their respective ceilings 412, 422,432, 442 may provide for gas removal from their respective channels 310, 320,330, 340. In some embodiments, gas outlets are disposed in a ceiling of achannel. In some cases, a gas outlet may be disposed in a lateral wall (e. g., aninside wall). A gas outlet may be disposed in a location away from an expectedflow of liquid within the channel. For example, the geometry shown in FIG. 4may be expected to result in segregation of the liquid phase to the ”outside” ofthe channel (e. g., downstream in the machine direction, or toward the bottom ofthe page as shown on FIG. 4). The gas outlets may be located away from thislocation to enhance the removal of the gas phase vs. the liquid phase in eachchannel. Gas outlets may be disposed at different longitudinal positions (withrespect to fluid flow). For example, gas outlets may be disposed at differentdistances (from the center of the forming wire, such as in the cross direction ofthe machine).
    [81] [0081] Gas outlets may be evacuated via a common manifold. In somecases, gas outlets may have different sizes (which may result in Variablepumping speeds associated with each channel). For example, an outer gas outlet(e. g., 410) may be larger than an inner gas outlet (e. g., 420) which may provide forincreased gas removal from first channel 410, which may have an entranceproximate to a more ”misty” spray comprising smaller droplets (as compared to34 127534011 (caim)second channel 320). In some cases, separate ducts (or even separatepumps/fans) are provided for separate gas outlets. In some cases, an adjustableoutlet size may be implemented. An outlet size may be adjusted by choosingdifferent size flaps that partially cover the outlet. An outlet size may be adjustedvia a throttle mechanism (that controllably blocks the outlet, such as a butterflyvalve).
    [82] [0082] In certain embodiments, a channel may include internal walls toenhance flow. In FIG. 4, internal walls 450 may be used to preferentially guidethe whitewater spray within a channel. A channel wall may be straight orcurved. In some embodiments, a wall is curved in two directions (e. g., a concavewall, such as a wall comprising a portion of a paraboloid, a hyperboloid, asphere, and the lil
    [83] [0083] FIGS. 5A and SB illustrate exemplary embodiments of channelgeometries. In some cases, optional horizontal walls 516 may be implementedwithin a channel (e. g., to control liquid flow in the channel). Horizontal walls 516may be located in a region of the channel at which the whitewater is expected tohave been segregated (into separate phases) and/or slowed down (e. g., viacurved portions prior to the horizontal walls). In such an implementation, wallsmay be designed to reduce turbulence and/or reduce velocity of the liquid phaseflowing out of the system. Various embodiments do not include such walls.35 127534011 (caim)
    [84] [0084] FIG. 5A illustrates an optional cleanout 520 (in this example,above the flume level) Which may be used to access an interior of the apparatus.FIG. 5B illustrates an optional cleanout 530 (in this case, below the flume level).Cleanout 530 may be coupled to an internal tube 540 (e. g., with holes), and maybe sealably accessed to extract material from the liquid within the apparatus. Inan embodiment, tube 540 is located in an eddy region, in which liquid flowingthrough the apparatus is expected to form eddy currents. Solids may settle outin an eddy region, and tube 540 may be used to extract (e. g., suck out) the settledsolids. In FIG. 5B, an optional baffle 716 is shown, and tube 540 is located on aleeward side of the baffle where solids may preferentially settle. A cleanout maybe disposed in a de-air system, a calming station, and/or other apparatus. FIG.5A illustrates an optional gate 611 (in this example, a replaceable gate midwaythrough a replacement motion).
    [85] [0085] A calming station may comprise one or more features designedto improve fluid flow, which may increase flume performance. A calmingstation may reduce turbulence in the liquid, which may reduce convection in theflume. Reduced convection may improve the rate at which small air bubbles riseto the surface (and leave the liquid phase), particularly for small air bubbles thatmight be ”dragged down” toward the bottom of the flume by convection withinthe liquid.36 127534011 (caim)
    [86] [0086] A calming station may dissipate or otherwise reduce energywithin the liquid. A calming station may make a Velocity profile (over a crosssection of the liquid) more uniform.
    [87] [0087] A calming station may comprise one or more baffles and/orgates configured to modify fluid flow within the calming station. Fluid flow maybe modified by a shape of the solid portion of a baffle or gate (e. g., of a slat).Fluid flow may be modified by a shape of an open portion (e. g., of a hole or a gapbetween slats.) A pattern may comprise one or more holes, one or more slats,and/or other features designed to affect fluid flow. The use of a term such as”hole” or ”slat” is for convenience. Various manufacturing techniques may beused to make different features having similar functionality (e. g., cutting holes ina plate may impart similar functionality as adding slats to a frame) and shouldnot be construed as limiting.
    [88] [0088] FIGS. 6A and 6B illustrate aspects of a calming station,according to some embodiments. A calming station may comprise an inlet 630(e. g., for liquid) and an outlet 640 (e. g., for liquid). A calming station maycomprise one or more gates (which may be fixed or adjustable) and/or one ormore baffles (which may be solid or have slats, holes, or other patterns). A gatemay have a pattern (e. g., of holes, slats, and the like). A pattern may vary over agate and/or baffle (e. g., horizontally, vertically). A gate or baffle may have a37 l2753,10ll (Calm)pitch (through its thickness) designed to impart a force on a fluid flowingthrough the gate/baffle.
    [89] [0089] In the example shown in FIGS. 6A and 6B, part of an optionalde-air system (300) is shown. A calming station may be implemented with orwithout a de-air system.
    [90] [0090] Air removal from the liquid phase (e. g., in the flume) oftenrequires the removal/reduction of small air bubbles from the liquid. Thesebubbles may be smaller than those that are readily removed during upstreamprocesses, and may require relatively long residence times before they can floatup and out of the flume. Turbulence and/or convection in the flume may”sweep” air bubbles that are close to the surface down into the flume, inhibitingtheir removal.
    [91] [0091] A calming station may be implemented to minimize convectionand/or turbulence in the flume, which may improve flume performance (e. g., theefficiency with which the so-called ”fan pump” pressurizes the stock for use inthe headbox). An increased efficiency of bubble removal from the liquid mayprovide for a smaller flume length and/or flume width, which may reducecomplexity and/or cost of an implementation. In an embodiment, a de-air systemremoves a first portion of air from the whitewater, condensing a spray from theforming wire into a liquid and sending the condensed liquid to a calming station.33 127534011 (caim)The liquid may comprise a small amount of remaining air bubbles. The calmingstation prepares the liquid for the flume (e. g., reducing turbulence, enhancingfiber removal, reducing maintenance times on fiber-removal filters (e. g., pre-fanpump) and the like). The flume then ”scavenges” at least a portion of theremaining air from the calmed water.
    [92] [0092] A calming station may be shaped (e. g., with internal surfaces,gates, slats, holes, baffles, and the like) to improve air removal from water in theflume. A bottom surface of a calming station may be shaped to smoothly directincoming water (e. g., from a de-air station) toward the flume. In someembodiments, a calming station may comprise eddies and/or stagnant zones thatenhance or implement the removal of residual solids (e. g., fibers) from the water(e. g., with a stagnant or eddy zone that induces settling of the fibers in a readily”cleanable” place). In some embodiments, a calming station and/or a de-airsystem has a ”clean design” that minimizes (or even eliminates) stagnant zonesand/or eddies. A calming station may include one or more gates and/or one ormore baffles, disposed, shaped, and having features designed to improve flumeperformance.
    [93] [0093] FIGS. 6A and 6B illustrate different configurations of anadjustable gate 610. In some cases, whitewater flow rates may vary significantly.
    [94] [0094] Adjustable gate 610 may be used to accommodate different flowVelocities prior to the flume. A pattern (e. g., of one or more slats 620 and/or holes(not shown)) may be designed to impart a desired effect (e. g., on the liquid) whenimmersed. A position of an adjustable gate may determine which portion of thefluid is affected at a particular time, enabling adaption of the system to variableflow velocities.
    [95] [0095] FIG. 6A shows a lowered gate, which may be used to slow or”brake” the liquid using one or more slats 620 (or alternately, remaining portionsafter holes have been machined). A ”braking” configuration may beadvantageous with high liquid velocities (e. g., with a disengaged turbine). FIG.6AB shows a raised gate, in which the liquid is not forced to flow through theslats/holes. Such a configuration may reduce turbulence and/or convection in aslow moving liquid, notwithstanding that it may not be optimal for a fast40 l2753,10ll (Calm)moving liquid. A raised gate may be used, for example, when a turbine isengaged. FIGS. 6A and 6B illustrate a pattern (in this example, of slats 620) thatvaries vertically. In this example, a lower portion of the slats has a crosssectional area (of the slats) that is larger than that of an upper portion, and gapdistances between slats are smaller. As a result, a lower portion of the gate mayinhibit flow more than the upper portion.
    [96] [0096] A gate may include a pattern of holes, slats, and/or otherfeatures that affects flow through or around the gate. The pattern may vary overa cross sectional area of the gate. The pattern may vary through the gate (e. g., apitch of the slats or holes through a relatively thick gate). A gate may beadjusted and/or changed out (e. g., during operation). A gate may be adjusted inresponse to turbine engagement/disengagement, a change in forming wire speed,a change in headbox Velocity, a change in stock concentration, a change in stockcomposition, and/or a change in other process parameters. An adjustable gatemay be implemented with a de-air system, a calming station, and/or otherapparatus.
    [97] [0097] FIG. 7 A is a schematic illustration of multiple gates, accordingto some embodiments. A calming station, a de-air system, and/or anotherapparatus may include one or more gates configured to modify a flow of fluid(gas or liquid). In an exemplary embodiment, a gate is disposed as part of a41 l2753,10l1 (Calm)calming station 600. In FIG. 7A, an adjustable gate 710 has a first pattern of slats620 comprising vertical slats in a lower portion and horizontal slats in an upperportion. The portions may have different slat sizes, different spacings betweenthe slats, and/or different slat pitches. The portions may be implemented withholes, rather than slats. In FIG. 7A, a fixed gate 712 has a second pattern of slats620, comprising horizontal slats having a varying slat width and slat spacing (ina vertical direction).
    [98] [0098] A high Velocity flow may result in a relatively larger differenceamong flow velocities (over a cross section of the calming station) than a smallvelocity flow. For example, an engaged turbine might result in relativelyuniform flow rates (entering the calming station) while a disengaged turbinemight result in some regions having very high flow and some regions havinglower flow. A gate or baffle design may accommodate these differences. In anembodiment, a portion of the gate or baffle that is ”upstream” with respect to themachine direction is more restrictive than a ”downstream” portion (e. g., thatreceives slower moving water). A vertically lower portion may have a denserpattern than a portion closer to the top of the flume. A first gate may cause fastlaminar flow to dissipate (e. g., impart turbulence) and a second gate may reducethis turbulence, resulting in a slow, minimally turbulent liquid exiting thecalming station.42 127534011 (caim)
    [99] [0099] Gates may have patterns of holes (not shown). An embodimentmay comprise two or more adjustable (e. g., replaceable gates). Anadjustable/replaceable gate may be adjusted/replaced while the machine isrunning, allowing for adjustment of the flow properties (e. g., into the flume)without requiring machine shutdown.
    [100] [00100] FIG. 7B is a schematic illustration of a baffle, according to someembodiments. A baffle 716 may be disposed in a fluid path (e. g., in a liquidpath) and may modify the flow of the fluid in an advantageous way. A bafflemay reduce the velocity of the fluid, reduce turbulence in the fluid, and the like.
    [101] [00101] A baffle and/or a gate may comprise one or more slats, gaps, orholes. A baffle and/or gate may have a pattern that varies over its cross sectionalarea and/or through its thickness. In some cases, a pattern of holes/slats in a”high speed” part of the flow may be different than that in a ”low speed” part ofthe flow. For example, a first pattern may be aligned with a channel expected toyield a high flow velocity (e. g., channel 340, FIG. 3) and a second pattern may bealigned with a channel expected to yield a lower flow velocity (e. g., channel 310,FIG. 3). A baffle may be solid, may comprise slats 620 (not shown), and/or holes.A baffle may be angled with respect to a surface to which the baffle is attached.
    [102] [00102] A baffle may be configured to create an eddy or substantiallystagnant zone. A baffle may be configured to reduce or prevent the creation of43 l2753,10ll (Calm)eddies or stagnant zones. In the example shown in FIG. 7B, exemplary baffle 716may be configured to create a relatively stagnant zone under certain flowconditions, and an optional cleanout 530 is disposed with its respective tube inthe stagnant zone. In an embodiment, a paper machine is operated at a flowcondition designed to induce settling of solids in a stagnant or eddy zone, andcleanout 530 is operated at or after that flow condition to extract the solids.
    [103] [00103] FIGS. 8A-8F illustrate exemplary patterns, according to someembodiments. Patterns of slats, gaps, or holes may be used for a baffle, a gate,and/or a combination thereof. For simplicity, the patterns in FIGS 8A-F aredescribe as if used in gates (which may be fixed or adjustable) and with thepattern described in terms of slats.
    [104] [00104] Gate 800 illustrates a higher slat density at a bottom of the gateand a different slat pattern in upper (horizontal) and lower (crosshatch) portions.Gate 810 illustrates a slat density that varies laterally (e. g., from denser patternassociated with a high velocity portion of the flow to a more open pattern for thelower velocity portion). Gate 820 illustrates a gate having a combination ofhorizontal and vertical slats, in this case with the vertical slats having ahorizontal variation in slat density. Gate 830 illustrates a crosshatch pattern ofslats. Gate 840 illustrates a gate having vertical slats (e. g., with different pitches).
    [105] [00105] A desired pattern may be chosen according to particularOperating conditions. In some cases, a machine is operated with a first gate at afirst condition, the first gate is swapped for a second gate, and the machine isoperated With the second gate at a second condition.
    [106] [00106] FIGS. 9A-F illustrate various slat cross sections, according tosome embodiments. A slat cross section may be chosen that imparts a preferredvelocity to the flowing fluid (e. g., pushes the fluid up, down, or to the side). FIG.9A illustrates a slat With a round cross section. FIG. 9B illustrates a slat With asquare (or diamond-shaped) cross section. A parallelogram or other shape mayalso be implemented. FIG. 9G illustrates a slat With an asymmetrical crosssection (e. g., a rounded face and a pointed face). FIG. 9D illustrates a curved slatcomprising a concave surface, which may include a Wing cross section. FIGS. 9Eand 9F illustrate flat slats having different diameter center sections.
    [107] [00107] An adjustable gate may comprise adjustable slats. Slats maythemselves be adjustable (e. g., pivotable around optional axes 910), which mayprovide for accommodation of different flow conditions.
    [108] [00108] FIG. 10 is a schematic illustration of adjustable slats, accordingto some embodiments. Gate 1010 may comprise one or more slats 1020 and alinkage 1030 configured to adjust the slats (e. g., adjust a pitch of the slats).
    [109] [00109] FIG. 11 illustrates a gate having slats with varying pitches,according to some embodiments. Gate 1100 may comprise slats 1110 havingdifferent pitches (e. g., with respect to fluid flow direction 1060). A first portion1120 of the gate may include a first pitch, and a second portion 1130 of the gatemay include a second pitch. The portions may be disposed with respect to eachother in a direction 1140 (e. g., horizontal, vertical). A first portion may bedisposed in a region expected to have a first flow velocity and a second portionmay be disposed in a region expected to have a second flow velocity. In anembodiment, first portion 1120 comprises a higher pitch (e. g., larger angles) andis disposed near a bottom of the gate and/or near a higher velocity side of thegate.
    [110] [00110] FIG. 12 illustrates an exemplary implementation with a turbine,according to some embodiments. A de-air system configured for use with aturbine may comprise one or more channel entrances having leading edges thatare shaped to ”wrap around” the turbine. A leading edge 350 of a channel (e. g.,46 l2753,10l1 (Calm)defining the entrance to the channel) may be shaped (e. g., curved) to ”Wraparound” a turbine. Such geometry may improve spray flow Within the channel,minimize splash-bacl< onto the forming Wire, and/or minimize fluidcommunication between the channels.
    [111] [00111] A modern turbine implementation may comprise a mechanismto engage or disengage the turbine. In some embodiments, an engagementmechanism comprises an adjustable mount configured to move the turbine intoor out of the spray ejected through the forming Wire. An engagementmechanism may comprise an adjustable guide plate 1250 configured to guide thespray ejected through the forming wire into (or away from) the turbine. Theguide plate may be actuated by an actuator 1260. The actuator may control aposition of the guide plate (e. g., with millimeter precision) to locate the guideplate in that position Which most efficiently transfers momentum from the sprayto the turbine. In some cases, the actuator may be used to engage/disengage theturbine. For example, positioning guide plate 1250 in a first position may directthe spray in a direction 1270 into the turbine (engaging the turbine), andpositioning guide plate 1250 in a second position may direct the spray in adirection 1280 away from the turbine (disengaging the turbine). In this example,de-air system 300 comprises a channel shape configured to accommodate thesprays from both the engaged and disengaged positions.47 127534011 (caim)
    [112] [00112] FIG. 12 illustrates certain features of a roof drain, according tosome embodiments. Certain machines may generate a significant ”mist” aroundthe forming section, which may deposit or even ”rain” onto various surfaces.Various apparatus may be disposed in an intrinsically ”wet” location (e. g.,”inside the loop” of forming Wire). A roof drain 1200 may collect water in amanner that improves safety and/or performance. A roof drain may beimplemented With a calming station, a de-air system, and/or other apparatus.
    [113] [00113] Roof drain 1200 may comprise a sloped roof 1210, Which maydescend to a gutter 1220. Gutter 1220 may collect Water landing on roof 1210 andguide the water to a drain 1230, Which may lead to an optional downspout 1240.
    [114] [00114] Various features described herein may be implementedindependently and/or in combination with each other. An explicit combinationof features does not preclude the omission of any of these features from otherembodiments. The above description is illustrative and not restrictive. ManyVariations of the invention will become apparent to those of skill in the art uponreview of this disclosure. The scope of the invention should, therefore, bedetermined not With reference to the above description, but instead should bedetermined with reference to the appended claims along with their full scope ofequivalents.43 127534011 (caim)
    权利要求:
    Claims (12)
    [1] 1. A calming station (600) configured for use with a forming section (10) of a papermachine (1) to reduce turbulence in a liquid flowing from the forming section into aflume (18) of the paper machine, the calming station comprising:a liquid inlet (630) configured to receive a liquid;a liquid outlet (640) configured to convey the liquid out of the calming station;anda gate (610, 710, 712, 800, 810, 820, 830, 840, 850) between the liquid inlet andliquid outlet, the gate comprising least one of :an adjustable gate, configurable among two or more differentpositions that alter the flow of the liquid in different ways; anda gate comprising a first portion having a first pattern of slats, gaps,or holes and a second portion having a second pattern of slats, gaps, or holes.
    [2] 2. The calming station of claim 1, further comprising a first gate having the adjustable gate and a second gate comprising the first and second portions.
    [3] 3. The calming station of claim 1, wherein the gate comprises the adjustable gate,the gate further comprising a first portion having a first pattern of slats, gaps, or holes, and a second portion having a second pattern of slats, gaps, or holes.
    [4] 4. The calming station of any of claims 1-3, wherein at least one gate comprises a pattern of slats, gaps, or holes that varies over at least one of a horizontal distance and a vertical distance. 49 12753,1011 (Calm)
    [5] 5. The calming station of any of claims 1-4, wherein at least one gate comprises afirst slat, gap, or hole having a first pitch with respect to a flow of fluid through the gate, and a second slat, gap, or hole having a second pitch.
    [6] 6. The calming station of any of claims 1-5, further comprising a baffle, particularly at a bottom of the calming station, the baffle shaped to redirect a flow of water moving along the bottom, particularly in a vertical direction. 5 O 12753,10l1 (Calm)
    [7] 7. The calming station of any of claims 1-6, further comprising a de-air system(300) for processing a whitewater spray (50) ejected from a forming wire (14) in theforming section, the de-air system disposed between the forming wire and the calmingstation and comprising: a first channel (310) defined at least in part by first walls (316), shaped to direct afirst portion of the whitewater spray away from the machine direction,particularly toward a side of the paper machine, particularly in a crossdirection (22), the first channel open at a first entrance (312) proximate tothe forming wire and terminating at a first liquid outlet (315) defined atleast in part by first terminal edges (318) of the first walls that arepreferably configured to extend beneath a surface of liquid water at a flumelevel; a first air outlet (410) in the first channel, the first air outlet providing for airevacuation from the first channel, preferably by a pump or fan (302), and a second channel (320) defined at least in part by second walls (326) shaped todirect a second portion of the whitewater spray away from the machinedirection, particularly toward a side of the paper machine, the secondchannel open at a second entrance (322) proximate to the forming wire andterminating at a second liquid outlet (325) defined at least in part by secondterminal edges (328) of the second walls that are preferably configured toextend beneath the surface of liquid water at the flume level; a second air outlet (420) in the second channel, the second air outlet providingfor air evacuation from the second channel, particularly by a pump or fan(302), preferably the same pump or fan as that of the first channel; wherein, between the entrances and liquid outlets, and excluding the air outlets, there is no substantial fluidic communication between the channels. 5 1 12753,1011 (Calm)
    [8] 8. The calming station of any of claims 1-6, further comprising a de-air system (300)for processing a whitewater spray (50) ejected from a forming wire (14) in the formingsection, the de-air system disposed between the forming wire and the calming stationand comprising one or more channels (310) having an entrance (312), a liquid outlet(315) and an air outlet (410), the channel shaped to redirect the whitewater spray awayfrom the machine direction to a lateral direction, particularly a cross direction (22), thechannel defined at least in part by channel walls (316) comprising side walls for which a majority, preferably substantially all, of the side wall is substantially vertical.
    [9] 9. The calming station of any of claims 1-6, further comprising a de-air system (300)for processing a whitewater spray (50) ejected from a forming wire (14) in the formingsection, the de-air system disposed between the forming wire and the calming stationand comprising one or more channels (310) shaped to redirect the whitewater sprayaway from the machine direction, particularly toward a lateral direction, particularly across direction (22), the channel defined at least in part by channel walls (316), andincluding an entrance (312), air outlet (410) and liquid outlets (315), wherein less than5% of a cross sectional area of the channel, preferably less than 1% of the cross sectionalarea, preferably less than 0.1%, preferably substantially none of the cross sectional area, is intersected by a free upstream end of a part.
    [10] 10. The calming station of any of claims 1-9, further comprising a turbine (20)coupled to a generator (21) and configured to harvest momentum of the whitewaterspray ejected through the forming wire to generate electricity, particularly a turbinecomprising an engagement mechanism configured to engage the turbine with ordisengage the turbine from the whitewater spray, preferably an engagement mechanismcomprising an adjustable guide plate that is controllably positionable to direct the spray into or away from the turbine. 52 127534011 (caim)
    [11] 11. A paper machine comprising: a calming station according to any of claims 1-10; a flume (18) disposed downstream of the calming station and configured toconvey liquid water away from the calming station, the liquid waterhaving a surface at a flume level; and a device, preferably an overflow edge (19), coupled to the flume and configured to control the flume level.
    [12] 12. A method for managing a flow of liquid water into a flume of a paper machine,the method comprising: providing an apparatus having:a liquid inlet coupled to a forming section of the paper machine,a liquid outlet coupled to the flume, andan adjustable gate configured to interact with liquid flowing through theapparatus and positionable among a plurality of positions having differentinteractions with the flowing liquid;determining a first flow rate of water out of the forming section; adjusting the adjustable gate to a first position for a flow of water at the first flowrate; determining a second flow rate of water different than the first flow rate; and adjusting the adjustable gate to a second position during a flow at the second flow rate. 53 127534011 (caim)
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    同族专利:
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    SE540223C2|2018-05-02|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    法律状态:
    优先权:
    申请号 | 申请日 | 专利标题
    SE1550683A|SE540223C2|2015-05-27|2015-05-27|Whitewater processing|SE1550683A| SE540223C2|2015-05-27|2015-05-27|Whitewater processing|
    US15/577,211| US10550517B2|2015-05-27|2016-05-26|Apparatus and method for processing white water in a paper machine|
    CN201680030818.5A| CN107667197B|2015-05-27|2016-05-26|Apparatus and method for treating white water in paper machine|
    PCT/EP2016/061935| WO2016189100A1|2015-05-27|2016-05-26|Apparatus and method for processing white water in a paper machine|
    PCT/EP2016/061936| WO2016189101A1|2015-05-27|2016-05-26|Apparatus an method for processing white water in a paper machine|
    EP16725529.8A| EP3303692A1|2015-05-27|2016-05-26|Apparatus and method for processing white water in a paper machine|
    BR112017025287A| BR112017025287A2|2015-05-27|2016-05-26|apparatus and method for processing white water in a papermaking machine|
    MX2017015035A| MX2017015035A|2015-05-27|2016-05-26|Apparatus an method for processing white water in a paper machine.|
    US16/725,921| US11028533B2|2015-05-27|2019-12-23|Apparatus and method for processing white water in a paper machine|
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